Rather than stressing its benefits, health promotion campaigns for the MMR vaccine should emphasise the protection that is lost by failing to have a child inoculated.

That’s according to PurvaAbhyankarand colleagues who said finding the most effective way to promote the triple jab is of vital importance because uptake has dropped in the UK in the wake of health fears that the vaccine is associated with side-effects such as autism.

One hundred and forty-two women, some were mothers, some not, with an average age of 35 years, were asked to imagine that they had to decide whether or not to have their child vaccinated with MMR. They were then presented with one of two possible messages about the MMR vaccine (alternative wording is in brackets):

“By vaccinating (not vaccinating) your child against mumps, measles and rubella, you will be able to (fail to) protect your child against contracting these diseases and take (will fail to take) advantage of a safe and lifelong immunization, which will make you feel less anxious (anxious) and safe (unsafe).”

Afterwards, the women presented with the message version that emphasised the protection and reassurance that would be lost if the vaccine were not given, were significantly more likely to say that they intended to give their child the vaccine, than were the women who read the alternative version. This difference was particularly pronounced among the women who had vaccinated their children previously in real life.

The researchers said their finding can be understood in terms of Prospect Theory – our willingness to take risks in the context of possible losses, in contrast to our aversion to taking risks in the context of possible gains. In other words, because people tend to see the MMR vaccine as risky, Prospect Theory suggests it is better to promote the vaccine in terms of what will be lost if that risk isn’t taken, rather than in terms of what might be gained – a prediction that is supported by the current results.

The researchers concluded their finding shows: “that interventions aimed at promoting high perceived risk prevention behaviours are likely to be more effective if designed in terms of messages emphasising the disadvantages of failing to perform the behaviour.”_________________________________